diff options
Diffstat (limited to 'drivers/pinctrl/sh-pfc/gpio.c')
| -rw-r--r-- | drivers/pinctrl/sh-pfc/gpio.c | 419 | 
1 files changed, 419 insertions, 0 deletions
diff --git a/drivers/pinctrl/sh-pfc/gpio.c b/drivers/pinctrl/sh-pfc/gpio.c new file mode 100644 index 00000000000..a9288ab01f7 --- /dev/null +++ b/drivers/pinctrl/sh-pfc/gpio.c @@ -0,0 +1,419 @@ +/* + * SuperH Pin Function Controller GPIO driver. + * + * Copyright (C) 2008 Magnus Damm + * Copyright (C) 2009 - 2012 Paul Mundt + * + * This file is subject to the terms and conditions of the GNU General Public + * License.  See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/device.h> +#include <linux/gpio.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/pinctrl/consumer.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#include "core.h" + +struct sh_pfc_gpio_data_reg { +	const struct pinmux_data_reg *info; +	unsigned long shadow; +}; + +struct sh_pfc_gpio_pin { +	u8 dbit; +	u8 dreg; +}; + +struct sh_pfc_chip { +	struct sh_pfc			*pfc; +	struct gpio_chip		gpio_chip; + +	struct sh_pfc_window		*mem; +	struct sh_pfc_gpio_data_reg	*regs; +	struct sh_pfc_gpio_pin		*pins; +}; + +static struct sh_pfc_chip *gpio_to_pfc_chip(struct gpio_chip *gc) +{ +	return container_of(gc, struct sh_pfc_chip, gpio_chip); +} + +static struct sh_pfc *gpio_to_pfc(struct gpio_chip *gc) +{ +	return gpio_to_pfc_chip(gc)->pfc; +} + +static void gpio_get_data_reg(struct sh_pfc_chip *chip, unsigned int offset, +			      struct sh_pfc_gpio_data_reg **reg, +			      unsigned int *bit) +{ +	int idx = sh_pfc_get_pin_index(chip->pfc, offset); +	struct sh_pfc_gpio_pin *gpio_pin = &chip->pins[idx]; + +	*reg = &chip->regs[gpio_pin->dreg]; +	*bit = gpio_pin->dbit; +} + +static unsigned long gpio_read_data_reg(struct sh_pfc_chip *chip, +					const struct pinmux_data_reg *dreg) +{ +	void __iomem *mem = dreg->reg - chip->mem->phys + chip->mem->virt; + +	return sh_pfc_read_raw_reg(mem, dreg->reg_width); +} + +static void gpio_write_data_reg(struct sh_pfc_chip *chip, +				const struct pinmux_data_reg *dreg, +				unsigned long value) +{ +	void __iomem *mem = dreg->reg - chip->mem->phys + chip->mem->virt; + +	sh_pfc_write_raw_reg(mem, dreg->reg_width, value); +} + +static void gpio_setup_data_reg(struct sh_pfc_chip *chip, unsigned idx) +{ +	struct sh_pfc *pfc = chip->pfc; +	struct sh_pfc_gpio_pin *gpio_pin = &chip->pins[idx]; +	const struct sh_pfc_pin *pin = &pfc->info->pins[idx]; +	const struct pinmux_data_reg *dreg; +	unsigned int bit; +	unsigned int i; + +	for (i = 0, dreg = pfc->info->data_regs; dreg->reg; ++i, ++dreg) { +		for (bit = 0; bit < dreg->reg_width; bit++) { +			if (dreg->enum_ids[bit] == pin->enum_id) { +				gpio_pin->dreg = i; +				gpio_pin->dbit = bit; +				return; +			} +		} +	} + +	BUG(); +} + +static int gpio_setup_data_regs(struct sh_pfc_chip *chip) +{ +	struct sh_pfc *pfc = chip->pfc; +	const struct pinmux_data_reg *dreg; +	unsigned int i; + +	/* Count the number of data registers, allocate memory and initialize +	 * them. +	 */ +	for (i = 0; pfc->info->data_regs[i].reg_width; ++i) +		; + +	chip->regs = devm_kzalloc(pfc->dev, i * sizeof(*chip->regs), +				  GFP_KERNEL); +	if (chip->regs == NULL) +		return -ENOMEM; + +	for (i = 0, dreg = pfc->info->data_regs; dreg->reg_width; ++i, ++dreg) { +		chip->regs[i].info = dreg; +		chip->regs[i].shadow = gpio_read_data_reg(chip, dreg); +	} + +	for (i = 0; i < pfc->info->nr_pins; i++) { +		if (pfc->info->pins[i].enum_id == 0) +			continue; + +		gpio_setup_data_reg(chip, i); +	} + +	return 0; +} + +/* ----------------------------------------------------------------------------- + * Pin GPIOs + */ + +static int gpio_pin_request(struct gpio_chip *gc, unsigned offset) +{ +	struct sh_pfc *pfc = gpio_to_pfc(gc); +	int idx = sh_pfc_get_pin_index(pfc, offset); + +	if (idx < 0 || pfc->info->pins[idx].enum_id == 0) +		return -EINVAL; + +	return pinctrl_request_gpio(offset); +} + +static void gpio_pin_free(struct gpio_chip *gc, unsigned offset) +{ +	return pinctrl_free_gpio(offset); +} + +static void gpio_pin_set_value(struct sh_pfc_chip *chip, unsigned offset, +			       int value) +{ +	struct sh_pfc_gpio_data_reg *reg; +	unsigned long pos; +	unsigned int bit; + +	gpio_get_data_reg(chip, offset, ®, &bit); + +	pos = reg->info->reg_width - (bit + 1); + +	if (value) +		set_bit(pos, ®->shadow); +	else +		clear_bit(pos, ®->shadow); + +	gpio_write_data_reg(chip, reg->info, reg->shadow); +} + +static int gpio_pin_direction_input(struct gpio_chip *gc, unsigned offset) +{ +	return pinctrl_gpio_direction_input(offset); +} + +static int gpio_pin_direction_output(struct gpio_chip *gc, unsigned offset, +				    int value) +{ +	gpio_pin_set_value(gpio_to_pfc_chip(gc), offset, value); + +	return pinctrl_gpio_direction_output(offset); +} + +static int gpio_pin_get(struct gpio_chip *gc, unsigned offset) +{ +	struct sh_pfc_chip *chip = gpio_to_pfc_chip(gc); +	struct sh_pfc_gpio_data_reg *reg; +	unsigned long pos; +	unsigned int bit; + +	gpio_get_data_reg(chip, offset, ®, &bit); + +	pos = reg->info->reg_width - (bit + 1); + +	return (gpio_read_data_reg(chip, reg->info) >> pos) & 1; +} + +static void gpio_pin_set(struct gpio_chip *gc, unsigned offset, int value) +{ +	gpio_pin_set_value(gpio_to_pfc_chip(gc), offset, value); +} + +static int gpio_pin_to_irq(struct gpio_chip *gc, unsigned offset) +{ +	struct sh_pfc *pfc = gpio_to_pfc(gc); +	unsigned int i, k; + +	for (i = 0; i < pfc->info->gpio_irq_size; i++) { +		const short *gpios = pfc->info->gpio_irq[i].gpios; + +		for (k = 0; gpios[k] >= 0; k++) { +			if (gpios[k] == offset) +				goto found; +		} +	} + +	return -ENOSYS; + +found: +	if (pfc->num_irqs) +		return pfc->irqs[i]; +	else +		return pfc->info->gpio_irq[i].irq; +} + +static int gpio_pin_setup(struct sh_pfc_chip *chip) +{ +	struct sh_pfc *pfc = chip->pfc; +	struct gpio_chip *gc = &chip->gpio_chip; +	int ret; + +	chip->pins = devm_kzalloc(pfc->dev, pfc->info->nr_pins * +				  sizeof(*chip->pins), GFP_KERNEL); +	if (chip->pins == NULL) +		return -ENOMEM; + +	ret = gpio_setup_data_regs(chip); +	if (ret < 0) +		return ret; + +	gc->request = gpio_pin_request; +	gc->free = gpio_pin_free; +	gc->direction_input = gpio_pin_direction_input; +	gc->get = gpio_pin_get; +	gc->direction_output = gpio_pin_direction_output; +	gc->set = gpio_pin_set; +	gc->to_irq = gpio_pin_to_irq; + +	gc->label = pfc->info->name; +	gc->dev = pfc->dev; +	gc->owner = THIS_MODULE; +	gc->base = 0; +	gc->ngpio = pfc->nr_gpio_pins; + +	return 0; +} + +/* ----------------------------------------------------------------------------- + * Function GPIOs + */ + +static int gpio_function_request(struct gpio_chip *gc, unsigned offset) +{ +	static bool __print_once; +	struct sh_pfc *pfc = gpio_to_pfc(gc); +	unsigned int mark = pfc->info->func_gpios[offset].enum_id; +	unsigned long flags; +	int ret; + +	if (!__print_once) { +		dev_notice(pfc->dev, +			   "Use of GPIO API for function requests is deprecated." +			   " Convert to pinctrl\n"); +		__print_once = true; +	} + +	if (mark == 0) +		return -EINVAL; + +	spin_lock_irqsave(&pfc->lock, flags); +	ret = sh_pfc_config_mux(pfc, mark, PINMUX_TYPE_FUNCTION); +	spin_unlock_irqrestore(&pfc->lock, flags); + +	return ret; +} + +static void gpio_function_free(struct gpio_chip *gc, unsigned offset) +{ +} + +static int gpio_function_setup(struct sh_pfc_chip *chip) +{ +	struct sh_pfc *pfc = chip->pfc; +	struct gpio_chip *gc = &chip->gpio_chip; + +	gc->request = gpio_function_request; +	gc->free = gpio_function_free; + +	gc->label = pfc->info->name; +	gc->owner = THIS_MODULE; +	gc->base = pfc->nr_gpio_pins; +	gc->ngpio = pfc->info->nr_func_gpios; + +	return 0; +} + +/* ----------------------------------------------------------------------------- + * Register/unregister + */ + +static struct sh_pfc_chip * +sh_pfc_add_gpiochip(struct sh_pfc *pfc, int(*setup)(struct sh_pfc_chip *), +		    struct sh_pfc_window *mem) +{ +	struct sh_pfc_chip *chip; +	int ret; + +	chip = devm_kzalloc(pfc->dev, sizeof(*chip), GFP_KERNEL); +	if (unlikely(!chip)) +		return ERR_PTR(-ENOMEM); + +	chip->mem = mem; +	chip->pfc = pfc; + +	ret = setup(chip); +	if (ret < 0) +		return ERR_PTR(ret); + +	ret = gpiochip_add(&chip->gpio_chip); +	if (unlikely(ret < 0)) +		return ERR_PTR(ret); + +	dev_info(pfc->dev, "%s handling gpio %u -> %u\n", +		 chip->gpio_chip.label, chip->gpio_chip.base, +		 chip->gpio_chip.base + chip->gpio_chip.ngpio - 1); + +	return chip; +} + +int sh_pfc_register_gpiochip(struct sh_pfc *pfc) +{ +	struct sh_pfc_chip *chip; +	unsigned int i; +	int ret; + +	if (pfc->info->data_regs == NULL) +		return 0; + +	/* Find the memory window that contain the GPIO registers. Boards that +	 * register a separate GPIO device will not supply a memory resource +	 * that covers the data registers. In that case don't try to handle +	 * GPIOs. +	 */ +	for (i = 0; i < pfc->num_windows; ++i) { +		struct sh_pfc_window *window = &pfc->windows[i]; + +		if (pfc->info->data_regs[0].reg >= window->phys && +		    pfc->info->data_regs[0].reg < window->phys + window->size) +			break; +	} + +	if (i == pfc->num_windows) +		return 0; + +	/* If we have IRQ resources make sure their number is correct. */ +	if (pfc->num_irqs && pfc->num_irqs != pfc->info->gpio_irq_size) { +		dev_err(pfc->dev, "invalid number of IRQ resources\n"); +		return -EINVAL; +	} + +	/* Register the real GPIOs chip. */ +	chip = sh_pfc_add_gpiochip(pfc, gpio_pin_setup, &pfc->windows[i]); +	if (IS_ERR(chip)) +		return PTR_ERR(chip); + +	pfc->gpio = chip; + +	/* Register the GPIO to pin mappings. As pins with GPIO ports must come +	 * first in the ranges, skip the pins without GPIO ports by stopping at +	 * the first range that contains such a pin. +	 */ +	for (i = 0; i < pfc->nr_ranges; ++i) { +		const struct sh_pfc_pin_range *range = &pfc->ranges[i]; + +		if (range->start >= pfc->nr_gpio_pins) +			break; + +		ret = gpiochip_add_pin_range(&chip->gpio_chip, +					     dev_name(pfc->dev), +					     range->start, range->start, +					     range->end - range->start + 1); +		if (ret < 0) +			return ret; +	} + +	/* Register the function GPIOs chip. */ +	if (pfc->info->nr_func_gpios == 0) +		return 0; + +	chip = sh_pfc_add_gpiochip(pfc, gpio_function_setup, NULL); +	if (IS_ERR(chip)) +		return PTR_ERR(chip); + +	pfc->func = chip; + +	return 0; +} + +int sh_pfc_unregister_gpiochip(struct sh_pfc *pfc) +{ +	int err; +	int ret; + +	ret = gpiochip_remove(&pfc->gpio->gpio_chip); +	err = gpiochip_remove(&pfc->func->gpio_chip); + +	return ret < 0 ? ret : err; +}  | 
